Freshwater crocodiles grow up to 10 feet (3m) long, but on average are about 1.5 metres long. They have a narrow snout, sharp teeth and webbed hind feet. The freshwater crocodile is generally brown in colour, however this will vary depending on their environment.
The freshwater crocodile is found throughout the northern regions of Australia, from Cape York Peninsular to the Kimberley's. They are found in both salt and freshwater billabongs, large river systems, lakes and swamps.
The freshwater crocodile feeds mainly on fish, crustaceans and insects. Being opportunistic they will also prey upon small mammals, birds and reptiles.
The females dig nest holes that are exposed on sandbars during the dry season from August through September. Mating occurs three to six weeks before laying. An average clutch is between 13-20 eggs and hatch after about 65-95 days. Egg laying usually occurs at night, and they are commonly eaten by monitor lizards and feral pigs. Eggs that are incubated at a temperature of 32°C and above will produce males, and temperatures of 20°C and lower produce female embryos. Temperatures of 30°C will produce embryos of both sexes.
The nests of eggs are fiercely guarded by the female crocodile and at the end of the incubation period, the mothers will carry the newly hatched young to the water in their mouths. The mothers then stay close to the young and protect them for a short period of time. In addition to being hole nesters, they are also sometimes called "pulse nesters" because all females in a given population will usually nest within a brief three week period each season.